Baumans, V., G. Dijkstra, and C.J. Wensing (1982). The effect of orchidectomy on gubernacular outgrowth and regression in the dog. International Journal of Andrology 5(4): 387-400. ISSN: 0105-6263.NAL Call Number: QP251.I55Abstract: To test whether the outgrowth and regression of the gubernaculum testis and consequently testicular descent are testis dependent, unilateral and bilateral orchidectomies were performed on foetal dogs at 49 days post coitum (p.c.), and on newborns at day 0 and day 3 after birth. Prior to these experiments the vascularisation of the testis, epididymis and gubernaculum had been studied to develop a method of orchidectomy, in which the vascularisation of the gubernaculum and epididymis was minimally damaged. After bilateral orchidectomy at 49 days p.c., outgrowth of the gubernaculum stopped completely, and the epididymis remained in its original abdominal position. After bilateral orchidectomy at birth, the descent of the remaining epididymis from an intra-abdominal to an extra-abdominal position was retarded, due to retarded regression of the gubernaculum. Bilateral orchidectomy 3 days after birth resulted in a slightly retarded gubernacular regression. After unilateral orchidectomies the effects were similar but less pronounced. It was concluded that the testis induces and maintains the outgrowth and initiates regression of the gubernaculum, thereby regulating the process of testicular descent. However, once the regression had started, it appeared to proceed more or less autonomously.Descriptors: castration, cell division, dogs, epididymis, male genitalia, organ weight, pregnancy, testis.

Bronson, R.T. (1981). Age at death of necropsied intact and neutered cats. American Journal of Veterinary Research 42(9): 1606-1608. ISSN: 0002-9645.NAL Call Number: 41.8 Am3ADescriptors: castration, cats, hysterectomy, age of death.

Bronson, R.T. (1982). Variation in age at death of dogs of different sexes and breeds. American Journal of Veterinary Research 43(11): 2057-2059. ISSN: 0002-9645.NAL Call Number: 41.8 Am3AAbstract: A retrospective study of necropsy data for 2,002 dogs showed that the mean age at death of neutered dogs of both sexes exceeded that of intact dogs, but the differences were not significant. A wide variation in mean age at death of 56 breeds and cross breeds, 3.0 to 9.9 years, was found. This variation was not correlated with mean breed body weight. An attempt was made to explain the variability by finding diseases to which dogs of the short-lived breeds were particularly susceptible. This was not possible in general, since the samples of each breed were small and the total number of diseases from which they died so large. Dogs of long-lived breeds died of diseases appropriate to their age, particularly cancer, 39% of the sample. In the sample as a whole, cancer accounted for 20% of deaths at 5 years and increased to and remained between 40% and 50% from 10 to 16 years of age.Descriptors: dog diseases mortality, age factors, castration veterinary, crosses, genetic, dogs, longevity, retrospective studies, sex factors, species specificity.

Brueschke, E.E., R.A. Kaleckas, J.R. Wingfield, T.J. Welsh, and L.J. Zaneveld (1980). Development of a reversible vas deferens occlusion device. VII. Physical and microscopic observations after long-term implantation of flexible prosthetic devices. Fertility and Sterility 33(2): 167-178. ISSN: 0015-0282.NAL Call Number: 448.8 F41Abstract: Flexible prosthetic devices developed previously to reversibly block sperm transport through the vas deferens were implanted in the vasa deferentia of dogs or kept in a semen bath for a 6-month period. Dimensional measurements, flow characteristics, leakage tests, and detent action force tests to displace the valve stem were performed with the valves. No changes occurred in any of these parameters with the exception of a decrease in the force required to change the position of the valve stem. This explains the occasional passage of spermatozoa through certain closed devices after they have been implanted for long periods of time. Histologic studies indicated that the same types of genital tract changes are associated with an implanted device as with vasectomy, and that they occur with approximately equal frequencies. Scanning electron microscope studies showed (1) excellent tissue ingrowth into the Dacron velour material of the implanted device; (2) the build-up of material, consisting in part of spermatozoa, in the device lumen and on the value stem; and (3) the absence of surface degradation of either the Silastic material or the valve stem of the device. It is concluded that no irreversible tissue damage is caused by the long-term implantation of flexible prosthetic devices into the vas deferens.Descriptors: male contraceptive devices, dogs, sperm transport block, vas deferens, epididymis, prostheses and implants.

Brueschke, E.E., L.J. Zaneveld, R. Rodzen, K. Mayerhoffer, M. Burns, and J.R. Wingfield (1975). Development of reversible vas deferens occlusive device: V. Flexible prosthetic devices. Fertility and Sterility 26(1): 40-52. ISSN: 0015-0282.NAL Call Number: 448.8 F41Abstract: In contrast to the results with rigid-ended prosthetic devices implanted in the vas deferens of the dog, effective sperm transport was obtained for prolonged periods of time with flexible-ended (all soft) devices. Such transport could be halted by device occlusion with clips or shuttle stem valves. Opening the devices resulted once again in the passage of spermatozoa, indicating that these devices may be potentially useful as reversible male contraceptives. More research is necessary to determine the cause of an overall decrease in sperm output after device implantations and to evaluate any adverse side effects of such devices. Dacron velour-covered suture rings on the devices permitted effective tissue ingrowth and prevented leakage or recanalization.Descriptors: cell movement, dogs, male, prostheses and implants, silicone elastomers, spermatozoa, stainless steel, vas deferens, vasectomy.

Csiszar, P. and E. Brath (1997). Minimally invasive laparoscopic surgery on experimental animal models. Acta Chirurgica Hungarica 36(1-4): 63-64. ISSN: 0231-4614.Abstract: Our goal was to find a very good model for gynecological laparoscopic operations. The main purpose of the operations was to perform the same types of laparoscopic operations as we use daily in our clinical practice at the Department of Obstetrics and Gynecology. UMSD. The uterus of female dogs seemed to be ideal for this work. In every experiment we carried out 10 different interventions on identical part of different dog uterus. The operations were performed at identical time period of day (a.m.). The weight of the female dogs were similar. The anaesthesia was also performed the same way in every case. The main purpose of the operations was to find some significant changes or differences between the 10 different surgical techniques. The hystological investigation were carried out with normal microscope and electron microscope.Descriptors: gynecological laparoscopy, sterilization, surgical procedures, animal models, comparison study, tubal sterilization.

Fahim, M.S., Z. Fahim, J. Harman, I. Thompson, J. Montie, and D.G. Hall (1977). Ultrasound as a new method of male contraception. Fertility and Sterility 28(8): 823-831. ISSN: 0015-0282.NAL Call Number: 448.8 F41Abstract: Twenty male cats were treated once or twice with 1 watt/sq cm of ultrasound for 10 minutes. Each of 24 male dogs received one to three treatments with 1 watt/sq cm for 10 minutes. Another six dogs were treated with 2 watts/sq cm for 15 minutes. Four Cebus apella monkeys were treated with the same dosage as that used for the cats and dogs. A dosage of 1 watt/sq cm for 10 minutes was also applied to four human patients without the use of anesthetics, and no pain or side effects were noted. In all treated animals as well as in human patients the results indicate that ultrasound significantly suppresses spermatogenesis according to the dosage and frequency of treatment, without any effect on Leydig cells or blood testosterone levels.Descriptors: cats, methods of contraception, dogs, Haplorhini, cebus monkeys, rats, seminiferous tubules, spermatogenesis, temperature, ultrasonics.

Fukuda, S. and H. Iida (2000). Effects of orchidectomy on bone metabolism in beagle dogs. The Journal of Veterinary Medical Science 62(1): 69-73. ISSN: 0916-7250.NAL Call Number: SF604.J342Abstract: The effects of orchidectomy on bone metabolism in male beagle dogs were examined using twelve 2-year-old dogs that were orchidectomized. The dogs' bilateral iliac bones, double-labeled with tetracycline and calcein for the histomorphometry, were obtained from three dogs prior to orchidectomy and at 3, 6, 9, and 12 months afterwards. The serum biochemical constituents related to bone metabolism were examined before and every month after orchidectomy. Between 1 and 6 months after orchidectomy, the value of serum testosterone decreased (1 month), while the levels of parathyroid hormone, calcitonin, total calcium, osteocalcin, and alkaline phosphatase activity increased significantly, indicating a high bone turnover. The mean trabecular thickness and the fraction of labeled osteoid surface decreased significantly 3 months after orchidectomy, but other histomorphometric parameters were unchanged. In the period 7-12 months after orchidectomy, the parathyroid hormone level increased ever and above that of the first 6-month period, while the levels of calcitonin, osteocalcin, alkaline phosphatase activity, and phosphorus decreased. The bone volume, mean trabecular thickness, and the fraction of labeled trabecular surface decreased significantly compared with the pre-orchidectomy values. These findings indicate an imbalance in bone metabolism (i.e. bone resorption > bone formation). These results indicate that a loss of bone volume accompanied the fall in sex hormone levels following orchidectomy and suggest that the orchidectomized dog is available as an animal model for studying osteoporosis caused by hypogonadism and the decline of sex functions in men.Descriptors: animal model, bone remodeling, effects of orchiectomy, testosterone, bone volume, sex hormones.

Gobello, C., H. Baschar, G. Castex, R.L. de la Sota, and R.G. Goya (2001). Dioestrous ovariectomy: a model to study the role of progesterone in the onset of canine pseudopregnancy. Journal of Reproduction and Fertility Supplement 57: 55-60. ISSN: 0449-3087.NAL Call Number: 442.8 J8222 Suppl.Abstract: It has been suggested that overt pseudopregnancy in bitches is caused by an increase in the concentration of serum prolactin as a result of an abrupt decrease in progesterone concentration in the late luteal phase. This hypothesis was tested by using ovariectomy at dioestrus as an experimental model. A total of 18 intact cross- and purebred bitches were used. Eleven animals were ovariectomized (day 0) between day 25 and day 40 of the oestrous cycle, and seven intact bitches were used as controls. Blood samples for determination of prolactin and progesterone concentrations were collected on days -1, 1, 2, 3 and 7 in the ovariectomized group, and on day 1 and day 7 in the control group. On day 7, the presence or absence of overt pseudopregnancy was recorded. The four ovariectomized bitches with a history of pseudopregnancy showed signs of overt pseudopregnancy (P < 0.01). On day 7, progesterone concentrations were significantly higher in the control than in the ovariectomized bitches (P < 0.01). The expected decrease in serum progesterone concentration after ovariectomy was similar in pseudopregnant bitches and non-pseudopregnant bitches. However, in pseudopregnant bitches, but not in non-pseudopregnant bitches, there was a marked increase (expressed as percentage change) in the concentration of prolactin between day -1 and day 7 (P < 0.01). It was concluded that the abrupt decrease in progesterone concentrations does not lead systematically to pseudopregnancy. Only in bitches predisposed to pseudopregnancy would an abrupt decrease in progesterone concentrations induce a substantial increase in prolactin concentrations, which in turn would trigger the typical signs of pseudopregnancy.Descriptors: dogs, female, animal models, ovariectomy, progesterone, prolactin, pseudopregnancy.

Howe, L.M., M.R. Slater, H.W. Boothe, H.P. Hobson, T.W. Fossum, A.C. Spann, and W.S. Wilkie (2000). Long-term outcome of gonadectomy performed at an early age or traditional age in cats. Journal of the American Veterinary Medical Association 217(11): 1661-1665. ISSN: 0003-1488.NAL Call Number: 41.8 Am3Abstract: OBJECTIVE: To determine long-term results and complications of gonadectomy performed at an early age (prepubertal) or at the traditional age in cats. DESIGN: Cohort study. ANIMALS: 263 cats from animal shelters. PROCEDURE: Cats that underwent gonadectomy were allotted to 2 groups on the basis of estimated age at surgery (traditional age, > or = 24 weeks old; prepubertal, < 24 weeks old). Adoptive owner information was obtained from shelter records, and telephone interviews were conducted with owners to determine physical or behavioral problems observed in the cats after adoption. Follow-up information was obtained from attending veterinarians for cats with complex problems or when owners were uncertain regarding the exact nature of their cat's problem. RESULTS: Compared with traditional-age gonadectomy, prepubertal gonadectomy did not result in an increased incidence of infectious disease, behavioral problems, or problems associated with any body system during a median follow-up period of 37 months. Additionally, the rate of retention in the original adoptive household was the same for cats that underwent prepubertal gonadectomy as those that underwent traditional-age gonadectomy. CONCLUSIONS AND CLINICAL RELEVANCE: Prepubertal gonadectomy may be performed safely in cats without concern for increased incidence of physical or behavioral problems for at least a 3-year period after gonadectomy.Descriptors: prepubertal gonadectomy, cats, animal welfare, animal behavior, age factors, follow-up studies.

Howe, L.M., M.R. Slater, H.W. Boothe, H.P. Hobson, J.L. Holcom, and A.C. Spann (2001). Long-term outcome of gonadectomy performed at an early age or traditional age in dogs. Journal of the American Veterinary Medical Association 218(2): 217-221. ISSN: 0003-1488.NAL Call Number: 41.8 Am3Abstract: OBJECTIVE: To determine long-term results and complications of gonadectomy performed at an early age (prepubertal) or at the traditional age in dogs. DESIGN: Cohort study. ANIMALS: 269 dogs from animal shelters. PROCEDURE: Dogs that underwent gonadectomy were allotted to 2 groups on the basis of estimated age at surgery (traditional age, > or =24 weeks old; prepubertal, < 24 weeks old). Adoptive owner information was obtained from shelter records, and telephone interviews were conducted with owners to determine physical or behavioral problems observed in the dogs since adoption. Follow-up information was obtained from attending veterinarians for dogs with complex problems or when owners were uncertain regarding the exact nature of their dog's problem. RESULTS: Prepubertal gonadectomy did not result in an increased incidence of behavioral problems or problems associated with any body system, compared with traditional-age gonadectomy, during a median follow-up period of 48 months after gonadectomy. Rate of retention in the original adoptive household was the same for dogs that underwent prepubertal gonadectomy as those that underwent traditional-age gonadectomy. Infectious diseases, however, were more common in dogs that underwent prepubertal gonadectomy. CONCLUSIONS AND CLINICAL IMPLICATIONS: With the exception of infectious diseases, prepubertal gonadectomy may be safely performed in dogs without concern for increased incidence of physical or behavioral problems during at least a 4-year period after gonadectomy.Descriptors: animal behavior, early age gonadectomy, ovariectomy, orchiectomy, prepubertal gonadectomy, dogs, animal shelter, questionnaires.

Hubbard, J.I., B.I. Hyland, and N.E. Sirett (1990). Stimulation of the LH release by naloxone in anaesthetized cats after ovariectomy. Neuroscience Letters 108(3): 295-302. ISSN: 0304-3940.NAL Call Number: QP351.N3Abstract: The effect of intravenous injections or infusions of the opioid receptor antagonist naloxone on the secretion of luteinizing hormone (LH) was studied in 18 spayed cats anaesthetized with Althesin. Effective injections significantly increased the LH concentration of plasma samples (taken every 10-15 min and measured by radio-immunoassay) to a peak 20-30 min after injection. The concentration thereafter declined exponentially (ke = 0.42), and, in 4/8 trials rose again significantly and declined again without further injection. The threshold dose was between 0.4 and 0.5 mg/kg. There did not appear to be a dose dependence of the effect above threshold. Infusion of naloxone at levels up to 5 mg/kg/h was effective in producing a pulsatile release of LH and repeated injections of threshold doses (0.5 mg/kg) could produce a maintained plateau and pulsatile release at frequencies comparable to pulse frequencies in vivo. Descriptors: anesthesia, animal, cats, dose-response relationship, female, luteinizing hormone, naloxone, ovariectomy.

Jochle, W. (1987). Zum Sexualzyklus der Hundin: Neuere Einsichten und Konsequenzen fur Therapie und Fortpflanzungskontrolle. [The sexual cycle in the bitch: recent insights and impact on therapy and reproduction control]. Tierärztliche Praxis 15(3): 295-300. ISSN: 0303-6286.NAL Call Number: SF603.V4Abstract: Present knowledge about the estrous cycle of the bitch has been reviewed from a morphological, endocrinological and clinical point of view. This cycle is truly biphasic, characterized by its slow motion. It includes pregnancy or pseudopregnancy, and lactation. Corpus luteum function and regression as well as endometrial recovery, following endometrial desquamation at about day 100 of the cycle, are finalized at about days 140 to 150. Soon thereafter, subclinical preparations for the next proestrus can be recognized. Prolactin seems to play an important role as a luteotrophic agent, beginning at about day 30 to 35 of the cycle. Inhibition of prolactin secretion can be used to induce abortion, or to inhibit lactation and to shorten the cycle, or to treat clinical anestrus. Late metestrus and subclinical proestrus, i.e. days 120 to 170 of the cycle, is the most suitable period of the cycle to initiate suppression of the cycle, i.e. prevention of the next estrus, by using progestins with the least tendency for side effects. Article in German.Descriptors: dogs, estrus synchronization, female, implications for contraception.Language of Text: German; Summary in English.

Kawakami, E., T. Tsutsui, M. Shimizu, H. Orima, M. Fujita, and A. Ogasa (1995). Comparison of the effects of chlormadinone acetate-pellet implantation and orchidectomy on benign prostatic hypertrophy in the dog. International Journal of Andrology 18(5): 248-255. ISSN: 0105-6263.NAL Call Number: QP251.I55Abstract: Five beagles out of 11 dogs aged 7-10 years with benign prostatic hypertrophy (BPH) were implanted subcutaneously with pellets of the synthetic anti-androgen chlormadinone acetate (CMA) at a dose of 10 mg/kg bodyweight. The remaining six dogs (one beagle and five mongrel dogs) underwent bilateral orchidectomy. Changes in prostatic volume, histological findings in the prostate and the testis, and peripheral plasma levels of LH, testosterone and oestradiol-17 beta (E2) were assessed up until 24 and 4 weeks after CMA-implantation and orchidectomy, respectively. Measurements of the size of the prostate and biopsies of the prostate were performed by laparotomy. Mean prostatic volume had decreased to 71% and 41%, respectively, of its pretreatment volume, by 4 weeks after CMA-implantation and orchidectomy, and was 49% and 47%, respectively, of pretreatment volume at 12 and 24 weeks after CMA-implantation. The clinical signs of BPH, e.g. haematuria, resolved within 2 weeks after either treatment. When the prostate was examined histologically 4 weeks after either treatment, hardly any evidence of active secretion (e.g. glandular epithelium projecting markedly into the lumen), was observed in CMA-implanted dogs, alveolar diameter and height of the glandular epithelium had decreased markedly and the glandular lumen had become very small in the orchidectomized dogs. By 12 weeks after CMA-implantation, degenerative and atrophic glands were observed in the prostate nearly the same as at 4 weeks after orchidectomy. In the testis the number of germ cells in the seminiferous tubules decreased markedly after CMA-implantation. The mean level of plasma LH at 4 weeks after orchidectomy had increased to 14.9 ng/ml, twice the value before operation. The mean levels of plasma testosterone and E2 at 4 weeks after CMA-implantation had decreased to 0.7 ng/ml and 9 pg/ml from 1.5 ng/ml and 15 pg/ml, the values before treatment, respectively. CMA-implantation resulted in poor semen quality. The results indicate that CMA-implantation at a dose of 10 mg/kg results in the same prostate-shrinking effect as orchidectomy.Descriptors: dogs, anti-androgen chlormadinone acetate, oral contraceptives, orchidectomy, comparison study, semen quality, prostate-shrinking effect, drug implants.

Lanevschi, A., J.W. Kramer, S.A. Greene, and K.M. Meyers (1996). Fibrinolytic activity in dogs after surgically induced trauma. American Journal of Veterinary Research 57(8): 1137-1140. ISSN: 0002-9645.NAL Call Number: 41.8 Am3AAbstract: OBJECTIVE: To determine whether alterations in the fibrinolytic pathway analytes, plasminogen (PLG), tissue plasminogen activator, and alpha 2-antiplasmin are significant in dogs subjected to minor and major surgical trauma. ANIMALS: 18 dogs in 3 groups of 6 each. PROCEDURE: Plasma fibrinolytic pathway analytes were measured in dogs with trauma of ovariohysterectomy (minor trauma) or orthopedic surgery (major trauma) and halothane anesthesia (control group). A commercial procedure adapted to a microtitration plate was used to measure the analytes. Blood was obtained 24 hours before anesthesia, at extubation (0 hours), and again at 2, 24, and 48 hours after extubation. An analyte quality-control strategy was maintained. RESULTS: In the major trauma group, there was a significant, transient, postsurgical decrease in PLG activity at 0 and 24 hours and a return to presurgical values by 48 hours. The minor trauma group had a similar trend without significant changes, including an increase in PLG values at 48 hours that exceeded the reference range. Antiplasmin values changed significantly in the major trauma group only. Tissue plasminogen activator values remained within the reference range. CONCLUSIONS: Tissue plasminogen activator was not considered a clinical marker of interest for detection of alterations in fibrinolysis after trauma. In contrast, plasma PLG and alpha 2-antiplasmin values may be useful in the evaluation of hemostatic complications of surgery. CLINICAL RELEVANCE: Identification of altered fibrinolysis in dogs undergoing traumatic surgery may provide a baseline for preventive pre-and postsurgical hemostatic care.Descriptors: fibrinolysis, hysterectomy, orthopedics, ovariectomy, wounds and injuries, anesthesia, antiplasmin analysis, biological markers, dogs, halothane, plasminogen, postoperative period, reference values, time factors.

Mahlow, J.C. (1999). Estimation of the proportions of dogs and cats that are surgically sterilized. Journal of the American Veterinary Medical Association 215(5): 640-643. ISSN: 0003-1488.NAL Call Number: 41.8 Am3Abstract: OBJECTIVE: To determine an estimate of the proportions of dogs and cats in Texas that are surgically sterilized and whether those proportions differed according to species and sex of the animal, level of responsibility of the owner, or geographic location. DESIGN: Cross-sectional study. ANIMALS: 43,831 dogs and cats > or = 6 months old. PROCEDURE: Information on sterilization rates was provided by 14 licensing agencies and 16 animal shelters in diverse regions of Texas. Univariate and multivariate analyses were used to compare sterilization rates among subpopulations of animals (dogs vs cats, males vs females, sheltered vs licensed, rural vs urban location). RESULTS: Overall, 12,893 (29.4%) of the animals (26.9% of dogs and 32.6% of cats) were sterilized. Proportions of animals sterilized were significantly different among subpopulations. CONCLUSIONS AND CLINICAL RELEVANCE: Although the cause of pet overpopulation is multifaceted, failure of owners to spay and castrate their animals is a major contributing factor. Significant differences in sterilization rates among subpopulations of dogs and cats suggest that organizations encouraging spaying and castration should use motivational techniques specific for the pet owners they are targeting.Descriptors: gonadectomy, sterilization statistics, dogs, cats, rural population, cross sectional study, owner responsibility, education.

Martin, R.B., R.L. Butcher, L.L. Sherwood, P. Buckendahl, R.D. Boyd, D. Farris, N. Sharkey, and G. Dannucci (1987). Effects of ovariectomy in beagle dogs. Bone 8(1): 23-31. ISSN: 8756-3282.NAL Call Number: RC930.B65Abstract: Beagle dogs 3-7 years old were ovariectomized (n = 9) or sham operated (n = 6) and followed for 48 weeks with measurements of body weight, tibial shaft bone mineral content (BMC), and serum biochemistry. Following killing, measurements were made of bone strength and histomorphometry. Ovariectomy (OX) significantly reduced serum estrone and estradiol concentrations and their variability from month to month. There was a transient decrease in cortical BMC of the OX dogs during the first 12 postoperative weeks but no difference between the groups after 48 weeks. Serum osteocalcin was elevated, but there was little effect on serum alkaline phosphatase, Ca, P, or calcitonin. OX increased the number of tetracycline-labeled osteons in cortical bone but reduced the percent trabecular surface labeled with tetracycline. OX produced no significant changes in the composition of the bones or loss of cortical area, but a statistically significant 15% trabecular bone loss occurred in the spine. However, bone strength had not been significantly affected at the time of sacrifice.Descriptors: disease models, animal, dogs, osteoporosis, ovariectomy, bone and bones analysis, calcium binding proteins, estradiol, osteocalcin, progesterone, spine.

Maute A.M., Koch D.A., and Montavon P.M. (2001). Perineale Hernie beim Hund - Colopexie, Vasopexie, Cystopexie und Kastration als Therapie der Wahl bei 32 Hunden. [Perineal hernia in dogs -- colopexy, vasopexy, cystopexy and castration as an alternative therapy in 32 dogs]. Schweizer Archiv Fur Tierheilkunde 143(7): 360-367. ISSN: 0036-7281.NAL Call Number: 41.8 SCH9 Abstract: In 32 male dogs colopexy, vasopexy, cystopexy and castration was performed for the treatment of perineal hernia. Recurrence rate in this study is 22%, what is comparable to other studies using different methods. The degree of severity and the number of complications is lower with this technique than with others. Enlargement of the prostate was evident in 59% and bladder retroflexion in 22% of the dogs. A celiotomy allows to recognize, assess, reduce and fix displaced organs which is not possible by using other methods. The aim is to regain the tubular structure of the ampulla recti and to fix prostate and bladder cranioventrally to the pelvic entrance. The castration performed at the same time causes the prostate gland to atrophy within 2-3 weeks, what makes the pelvic entrance even wider and the dogs return to normal defecation.Descriptors: hernia, perineum, surgery, treatment.Language of Text: German; Summary in English.

Minami, S., Y. Okamoto, H. Eguchi, and K. Kato (1997). Successful laparoscopy assisted ovariohysterectomy in two dogs with pyometra. The Journal of Veterinary Medical Science 59(9): 845-847. ISSN: 0916-7250.NAL Call Number: SF604.J342Abstract: Two dogs with pyometra were treated by laparoscopy assisted ovariohysterectomy. Hemostasis of the mesovarium was achieved with an ultrasonic scalpel and hemoclips. Both ovaries and the uterus were exposed via a 10-mm caudal port that was enlarged to 3 cm and the uterine cervix was excised after ligation of the uterine arteries. These cases were the first report on ovariohysterectomy for pyometra by laparoscopy assisted surgery in the veterinary field.Descriptors: pyometra, ovariectomy, hemostasis, laparoscopy, uterine diseases, dogs.

Mojzisova, J., R. Hromada, I. Valocky, S. Paulik, V. Hipikova, V. Bajova, S. Posivakova, and A. Bugarsky (2003). Effect of ovariohysterectomy on canine postsurgical leukocyte function. Acta Veterinaria Hungarica 51(2): 219-227. ISSN: 0236-6290.NAL Call Number: 41.8 Ac83Abstract: The effect of surgery on phagocytic activity of blood leukocytes and mitogen-induced blastogenesis of lymphocytes was studied in fourteen dogs. Simple ovariohysterectomy with anaesthesia induced by ketamine and xylazine or by ketamine, xylazine and halothane caused a short nonsignificant depression of phagocytic activity that persisted for four hours after surgery. Ingestion capacity of leukocytes decreased significantly immediately after surgery. Mitogen-induced blastogenesis of lymphocytes was depressed significantly in the first 48 hours and despite partial recovery this parameter did not reach the value of the control groups until the end of observation (7 days). A more conspicuous decrease of blastogenic response of blood lymphocytes to mitogens was found after the use of ketamine and xylazine in a dose maintaining anaesthesia. Anaesthesia with ketamine and xylazine in the lower dose and maintained with halothane resulted in a later improvement of the blastogenic response of lymphocytes. Descriptors: dissociative anesthetics, dogs, halothane, hysterectomy, ketamine, leukocyte count, leukocytes, ovariectomy, phagocytosis, xylazine.

Muller, S.C., J.T. Hsieh, T.F. Lue, and E.A. Tanagho (1988). Castration and erection. An animal study. European Urology 15(1-2): 118-124. ISSN: 0302-2838.Abstract: Castrated dogs (n = 3) need a much higher threshold level of energy to induce erection by electrical stimulation of the cavernous nerve than noncastrated animals (n = 24). In addition the resulting quality of erection, measured as maximal intracavernous pressure (pCC) versus peak systolic blood pressure (BP), was weaker in castrated dogs (pCC = 57% of BP on average) than in noncastrated dogs (pCC = 80% of BP on average). A high venous outflow from the corpora cavernosa in castrated dogs can also explain the shorter duration of erection. This experimental model excludes the interference of subjective factors, such as erotic stimuli and libido on erection, and it seems that androgen deficiency has a direct effect on the neurophysiology of the erectile tissues resulting in a higher tonus of the detumescence factors, which can be explained by an incomplete relaxation of the sinusoidal smooth muscle.Descriptors: androgens physiology, orchiectomy, penile erection, penis physiology, dogs, electric stimulation.

Nassar, R. and J.E. Mosier (1982). Feline population dynamics: a study of the Manhattan, Kansas, feline population. American Journal of Veterinary Research 43(1): 167-70. ISSN: 0002-9645.NAL Call Number: 41.8 Am3AAbstract: Analysis of the age-specific birth and survival rates and the age distribution in the pet population of cats in Manhattan, Kansas, revealed that the rate of population change (lambda) was about 1.18. This means that under present birth and death rates, the cat population can increase by about 18% per year. In reality, the increase may not be as high since pet ownership may not increase by as much. The frequency of spayed females of reproductive age in the Manhattan population was about 59%. This may not be sufficient to curb population growth. With the present age-specific survival rates, about 88% of the females should be spayed if the population is to remain stable. The ratio of people to cats in Manhattan was estimated to be 5.2:1. The average number of cats per household was 0.508. The percentage of households with cats was 28 with an average of 1.74 cats per household. In comparison, the average number of dogs per household was 0.43 and the percentage of households with dogs was 43 with an average of 1.36 dogs per household. The methods used in this study are useful for collecting and analyzing data to be used by governmental bodies and veterinarians concerned with proposals to regulate pet population growth and reproduction.Descriptors: cats, castration veterinary, Kansas, longevity, mortality, population control, population dynamics.

Nassar, R., J.E. Mosier, and L.W. Williams (1984). Study of the feline and canine populations in the greater Las Vegas area. American Journal of Veterinary Research 45(2): 282-7. ISSN: 0002-9645.NAL Call Number: 41.8 Am3AAbstract: Analysis of household dogs and cats, based on age-distribution data and on age-specific birth and survival rates, as well as on pet source, indicated that the dog and cat populations are stable and not increasing in size (lambda congruent to 1). Roaming dogs and cats euthanatized at the pound represented about 5.7% and 8.1% of the estimated dog and cat populations, respectively. The death at the pound seems to be effective in checking pet population growth. Among pets acquired, 84% were less than 1 year of age for dogs as compared with 88% for cats. Breeders and pet shops supplied about 7% of cats and 17% of dogs. About 10% of cats and 10% of dogs were acquired at the pound, while 6.4% of dogs and 14% of cats were acquired as stray. About 45% of dogs and 41% of cats were acquired from pet owners. Some dogs (12.46%) and cats (12%) were imported from outside the Las Vegas area. Of dogs and cats below 2 months of age, 33% and 19.5%, respectively, came from breeders or pet shops or were imported from outside the area. Seventeen percent of unspayed female dogs and 16% of unspayed female cats reproduced. The percentages of spayed females were 77 for dogs and 86 for cats. Forty-five percent of the dogs and 48% of the cats were males. Among dogs at the shelter, 2% were neutered and 26% spayed. At the pound, 24% of dogs were small breeds, 24% medium size breeds, and 52% large breeds.Descriptors: cats, dogs, age factors, animals, domestic, castration, population control, population dynamics, questionnaires.

Nomura, K. and T. Makino (1997). Effect of ovariectomy in the early first half of the diestrus on induction or maintenance of canine deciduoma. The Journal of Veterinary Medical Science 59(3): 227-230. ISSN: 0916-7250.NAL Call Number: SF604.J342Abstract: The effect of ovariectomy in the early first half of the diestrus was examined on the induction or maintenance of suture-induced canine deciduoma. Ovariectomy immediately, or some days, after the insertion of suture had no effect on the induction or maintenance of deciduoma. Even when ovariectomy was performed within 4 days before insertion, deciduoma could be induced in spite of there being no ovary. However, when ovariectomy was done 4 or more days before suture insertion, the rate of deciduoma was decreased or no deciduoma was induced. These results indicate that the influence of the ovary on the endometrium may persist for at least 4 days after ovariectomy. Ovariectomy after the suture insertion had few effects. It is suggested that canine uterine glands in the early first half of the diestrus maintain a certain degree of self-proliferative ability even after ovariectomy, and thus canine deciduoma is not as dependent on the ovary that of the rodentia.Descriptors: ovariectomy, body weight, cell division, decidua, diestrus, laparotomy, ovary, female, suture techniques.

Okkens, A.C. (1981). Ovario-hysterectomie bij de hond. [Ovariohysterectomy in dogs]. Tijdschrift Voor Diergeneeskunde 106(22): 1129-1141. ISSN: 0040-7453.NAL Call Number: 41.8 T431Abstract: A brief introductory part is followed by a discussion of the age of the bitch and that stage of the oestrous cycle, during which ovariohysterectomy can best be performed. The various indications for ovariectomy and ovariohysterectomy are reviewed. A number of important anatomical features are briefly referred to and the technique of ovariohysterectomy is described in detail. Attention is paid to a number of complications such as haemorrhage during or after operation and the escape of infected contents of the uterus into the abdominal cavity. Finally, the possible effects of ovariohysterectomy, such as a gain in weight, a change of character, incontinence of urine and the appearance of an infantile vulva associated with pruritus vulvae, are discussed.Descriptors: age factors, animal behavior, methods of castration, body weight, postoperative complications, uterus, hysterectomy, dogs.Language of Text: Dutch; Summary in English.

Ozanne-Smith, J., K. Ashby, and V.Z. Stathakis (2001). Dog bite and injury prevention--analysis, critical review, and research agenda. Injury Prevention 7(4): 321-326. ISSN: 1353-8047.Abstract: OBJECTIVES: To analyze Australian dog bite injury data and make international comparisons; to review risk and protective factors relating to the dog, injured person, and environment; and to recommend action for prevention and research. METHODS: Australian dog bite injury data, complemented by detailed Victorian and regional data from routine health records and vital statistics, were analyzed to determine incidence, severity, nature, circumstances, and trends. International comparison data were extracted from published reports. Risk and protective factor studies were selected for review from electronic and bibliographic searches where data were recent, sample sizes substantial, and bias limited. RESULTS: The Australian dog bite death rate (0.004/100,000) is lower than both the United States (0.05-0.07/100,000) and Canadian rates (0.007/100,000). Victorian hospitalized trend rates were stable between 1987 and 1998, but there was a decline for children <5 years (p=0.019) corresponding with a reduction in dog ownership. Children 0-4 years have the highest rate of serious injury, particularly facial. Adults have longer hospitalizations, most frequently for upper extremity injury. Risk factors include: child, males, households with dogs, certain breeds, male dogs, home location, and leashed dog. CONCLUSIONS: Dog bite rates are high and it may therefore be assumed that current preventative interventions are inadequate. Responsible dog ownership, including separating young children from dogs, avoiding high risk dogs, neutering, regulatory enforcement, and standardized monitoring of bite rates are required. Controlled investigations of further risk and protective factors, and validated methods of breed identification, are needed.Descriptors: animals, Australia, bites, dogs, hospitalization, human, risk factors, responsible dog ownership.

Robbins, M.A. and H.S. Mullen (1994). En bloc ovariohysterectomy as a treatment for dystocia in dogs and cats. Veterinary Surgery 23(1): 48-52. ISSN: 0161-3499.NAL Call Number: SF911.V43Abstract: En bloc ovariohysterectomy, a technique that involves ovariohysterectomy before hysterotomy and removal of the neonates, was performed on 63 animals (37 dogs and 26 cats). Intraoperative complications were limited to 1 cat that bled excessively during surgery and was later found to have a clotting disorder. Postoperative complications included anemia that required blood transfusion in 3 cats, uroperitoneum in 1 dog, and death in 1 cat. The rate of neonatal survival (75% for dogs and 42% for cats) was similar to that documented by previous studies of medical and surgical management of dystocia. We concluded that en bloc ovariohysterectomy is a safe and effective alternative to cesarean section for surgical treatment of dystocia in dogs and cats.Descriptors: dog diseases, cat diseases, reproductive disorders, surgery, postoperative complications, parturition complications, dystocia, hysterectomy, ovariectomy, dogs, cats.

Santen, R.J., E. Samojlik, L. Demers, and E. Badder (1980). Adrenal of male dog secretes androgens and estrogens. American Journal Of Physiology 239(2): E109-E112. ISSN: 0002-9513.NAL Call Number: 447.8 Am3Abstract: In the absence of functioning gonads, the adrenal is an important source of androgens and estrogens. In order to precisely quantitate the adrenal secretion rates of the sex steroids, we cannulated the adrenal veins and measured venous blood flow and arterial venous steroid gradients in adult male beagle dogs under pentobarbital anesthesia. Celite chromatography and specific radioimmunoassays were utilized to measure steroid levels. During basal conditions, the adrenal produced larger amounts of the androgens (667 ng/min of androstenedione, 5.45 ng/min of testosterone, and 3.43 ng/ min of dihydrotestosterone) than of the estrogens (1.245 ng/min of estradiol and 0.239 ng/min of estrone. These secretion rates were 20- to 50,000-fold less than that of cortisol (12,360 ng/min). Studies were also carried out during adrenal suppression with hydrocortisone to block ACTH release and with the adrenal steroidogenesis inhibitor, aminoglutethimide, plus hydrocortisone. The secretion rates of each androgen measured fell during ACTH inhibition. Significant suppression of estrone and estradiol, however, required addition of aminoglutethimide. This study provides direct evidence that the adrenal in the male dog can secrete estrogens, a previously controversial issue.Descriptors: adrenal glands, androstenediols, androstenols, castration, dogs, drug therapy, estradiol, sex factors, testosterone, estrogens.

Scott, K.C., J.K. Levy, S.P. Gorman, and S.M. Newell (2002). Body condition of feral cats and the effect of neutering. Journal of Applied Animal Welfare Science 5(3): 203-213. ISSN: 0002-9645.NAL Call Number: 41.8 Am3AAbstract: Considerable debate exists regarding the most appropriate methods for controlling feral cat populations, both from humane and logistical points of view. The physical condition of feral cats has not been reported, and it is not known if these cats benefit from neutering. This study investigates the body condition of feral cats by measuring body weight (BW), body condition score (BCS; Burkholder, 2000; Laflamme, Kealy, & Schmidt, 1994), and falciform fat pad. The study includes lateral abdominal radiographs taken at the time of neutering of 105 adult feral cats for measurement of falciform fat pad depth and area. At that time we also assessed BW and BCS. One year later we assessed the effects of neutering on body condition by evaluating a subsample of 14 cats. At the time of surgery, the cats were lean but not emaciated (BW 3.1 +/- 0.9 kg; BCS 4 +/- 1; based on a 1 to 9 scale ranging from 1 [emaciated] to 9 [grossly obese]). Falciform fat pad depth and area averaged 7.1 mm and 197.4 mm2, respectively, indicating a small amount of fat. Fourteen cats, reevaluated 1 year after neutering, increased 260% + 90% in falciform fat pad depth, 420% +/- 390% in fat pad area, 40% +/- 4% in BW, and 1 level in BCS ranking (1 to 9 scale; all differences p <.001). Similar to confined socialized cats, feral cats gained significant weight and body fat after neutering.Descriptors: feral cat population control, castration, neutering, body condition score, adipose tissue, body weight.

Sinowatz, F. (1984). Early changes in the dog prostate after castration. An ultrastructural study. [Fruehe Veraenderungen an der Prostata des Hundes nach Kastration. Eine feinstrukturelle Untersuchung]. Acta Anatomica 120(3): 103-107. ISSN: 0001-5180.NAL Call Number: 444.8 Ac8ZAbstract: Using electron microscopic techniques the prostate glands of male Beagle dogs were studied 3 days after castration. At this time marked differences in the extent of alterations of the glandular epithelium were observed: Whereas several acini showed only minor changes with reduction of epithelial height and diminution of secretory granules, many acini were severely affected with pronounced alteration of cellular structure and accumulation of large lipid droplets. A constant feature was the stimulation of the basal cells of the grandular epithelium. Additionally, in some areas of the gland aggregations of stimulated basal cells forming an acinus-like structure with a slit-like lumen were found. Our study shows that castration leads to marked alterations of prostatic epithelium within a short time. Androgen deprivation causes regressive changes of secretory epithelial cells, but clearly stimulates the basal cell population.Descriptors: dogs, epithelium, male, electron microscopy, postoperative period, prostate, prostatectomy.Language of Text: German; Summary in English.

Sorenmo, K.U., F.S. Shofer, and M.H. Goldschmidt (2000). Effect of spaying and timing of spaying on survival of dogs with mammary carcinoma. Journal of Veterinary Internal Medicine 14(3): 266-270. ISSN: 0891-6640.NAL Call Number: SF601.J65Abstract: The risk of developing mammary gland tumors in dogs is significantly decreased by ovariohysterectomy at an early age. However, previous studies have not found a benefit to ovariohysterectomy concurrent with tumor removal in dogs with established mammary gland tumors, suggesting that the progression of these tumors is independent of continued estrogen stimulation. The purpose of this study was to evaluate the effect of spaying and of the timing of spaying on survival in dogs with mammary gland carcinoma. Signalment, spay status and spay age, tumor characteristics, treatment. survival, and cause of death of 137 dogs with mammary gland carcinoma were analyzed. The dogs were classified into 3 groups according to spay status and spay time: intact dogs, dogs spayed less than 2 years before tumor surgery (SPAY 1), and dogs spayed more than 2 years before their tumor surgery (SPAY 2). Dogs in the SPAY 1 group lived significantly longer than dogs in SPAY 2 and intact dogs (median survival of 755 days, versus 301 and 286 days, respectively, P = .02 and .03). After adjusting for differences between the spay groups with regard to age, histologic differentiation, and vascular invasion, SPAY 1 dogs survived 45% longer compared to dogs that were either intact or in the SPAY 2 group (RR = .55; 95% CI .32-.93; P = .03). This study reveals ovariohysterectomy to be an effective adjunct to tumor removal in dogs with mammary gland carcinoma and that the timing of ovariohysterectomy is important in influencing survival.Descriptors: dog diseases, hysterectomy, mammary neoplasms, animal mortality, ovariectomy, disease progression, dogs, animal surgery, epidemiology, retrospective studies, survival analysis, time factors.

Spain, C.V., J.M. Scarlett, and S.M. Cully (2002). When to neuter dogs and cats: a survey of New York state veterinarians' practices and beliefs.Journal of the American Animal Hospital Association 38(5): 482-488. ISSN: 0587-2871.NAL Call Number: SF601.A5Descriptors: veterinarians, small animal practice, cats, dogs, castration, ovariectomy, age, surveys, New York.

Vannozzi, I., C. Benetti, and A. Rota (2002). Laparoscopic cryptorchidectomy in a cat. Journal of Feline Medicine and Surgery 4(4): 201-203. ISSN: 1098-612X.NAL Call Number: SF985.J68Abstract: Several techniques for castration of cryptorchid cats have been described. In this case report, the use of laparoscopy for castration of a bilateral cryptorchid cat (with testes located in the abdomen) is described. Three trocars were inserted into the abdominal cavity, the testicles were easily identified adjacent to the urinary bladder. Haemostasis of the gubernaculum testis and spermatic cord was achieved with bipolar cauterisation. The testicles were easily removed in approximately 20 min. To the authors' knowledge this is the first report of the use of laparoscopy for the treatment of cryptorchidism in cats.Descriptors: laparoscopic castration, cryptorchidism, cats, orchiectomy methods.

Volpe, P., B. Izzo, M. Russo, and L. Iannetti (2001). Intrauterine device for contraception in dogs. The Veterinary Record 149(3): 77-79. ISSN: 0042-4900.NAL Call Number: 41.8 V641Abstract: A new intrauterine device for contraception was tested on nine bitches. After it had been implanted, the bitches were mated but none of them became pregnant. Over a two-year period no side effects were observed, except in a bulldog bitch in which signs of oestrus persisted until the device had been removed.Descriptors: contraception, intrauterine devices, dogs.

Zielonka, T.M., D. Charpin, P. Berbis, P. Luciani, D. Casanova, and D. Vervloet (1994). Effects of castration and testosterone on Fel dI production by sebaceous glands of male cats: I--Immunological assessment. Clinical and Experimental Allergy 24(12): 1169-1173. ISSN: 0954-7894.Abstract: Fel dI is produced by salivary and sebaceous glands. Hormonal control of sebum production is clearly established. The influence of cat castration and supplementary treatment with testosterone on the production of sebum and Fel dI in cat skin have been researched in this study. On day 1, 12 male cats were anaesthetized and three skin areas carefully shaven. Then the level of lipids on skin surface was measured by means of a photometric method. Finally, the three areas of skin were washed with 5ml of distilled water through a plastic cylinder. Fel dI collected in the washes was measured with a two-site monoclonal antibody based ELISA. On day 2, six cats were castrated, the other six were used as a control group. Two and 4 weeks later, the levels of lipids and Fel dI in skin washes were measured again in all cats. On day 30, the six castrated cats were injected intramuscularly with prolonged-action testosterone. Two weeks later, quantification of lipids and Fel dI in all animals was repeated. Sebum and Fel dI levels decreased in all castrated animals. Injecting the castrated cats with testosterone led to a significant increase in sebum and Fel dI production. Our findings indicate that Fel dI production is influenced by the production of hormones.Descriptors: allergens, animals, monoclonal antibodies, castration, cats, enzyme-linked immunosorbent assay, glycoproteins, sebaceous glands.